Using ContourPlot when between x and y variables there is a constriant

To: mathgroup at smc.vnet.net

Subject: [mg69353] Using ContourPlot when between x and y variables there is a constriant

From: "diego.aristizabal" <daristi at gmail.com>

Date: Thu, 7 Sep 2006 23:58:54 -0400 (EDT)

Hi,
I have a problem with the command ContourPlot. The point is that I want
to contour plot a function which is real defined only for x>2y. In
other words what I want to plot is something like this:
ContourPlot[f(x,y),{x,xmin,xmax},{y,2*x,xmax}]. The problem is that
Mathematica does not understand the lower bound on y when specified as
2*x. I appreciate some help.
Diego.